干旱区生态环境知识资源中心(Arid): 两种荒漠植物叶片脱水下水分生理和PSⅡ活性特征

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	两种荒漠植物叶片脱水下水分生理和PSⅡ活性特征
其他题名	Characteristics of Leaf Dehydration on Water Relation and Photosystem Ⅱ Activity in Two Desert Plants
	鲁建荣 1; 李向义 1; 薛伟 1; 林丽莎 1; 李磊 1; 张新林 2
来源期刊	西北植物学报
ISSN	1000-4025
出版年	2013
卷号	33 期号:7 页码:1427-1434
中文摘要	以塔克拉玛干南缘的优势物种疏叶骆驼刺(Alhagi sparsifolia)和引进种大果白刺(Nitraria roborowskii)的离体叶片为实验材料,比较了不同水分状况下水势、气孔导度和叶绿素荧光参数的变化特征。结果显示:(1)大果白刺在脱水胁迫初期气孔导度值(G_s)高达495.7mmol.m~(-2).s~(-1),相对含水量(RWC)>96%时G_s降幅较小,维持较高气孔开度进行光合作用;骆驼刺气孔对脱水胁迫反应较灵敏,G_s值控制在180mmol.m~(-2).s~(-1)以内且G_s总体下降缓慢。(2)大果白刺在RWC>84%时水势高于骆驼刺并保持平稳下降,骆驼刺始终保持较缓慢下降趋势。(3)二者叶片气孔导度与水势绝对值均呈负指数回归关系,-2.2Mpa为大果白刺水势临界点,未发现骆驼刺有明显临界点。(4)二者的叶绿素荧光参数在脱水胁迫下均表现为初始荧光F_0显著上升,PSⅡ最大光化学效率F_v/F_m和潜在活性中心F_v/F_0值下降;骆驼刺的单位反应中心捕获的能量(TR_o/RC)和单位反应中心数目(RC/CS_o)呈波动变化,大果白刺在RWC<78%时各项荧光比活性值急剧上升且荧光曲线转为平台型。研究表明,骆驼刺具有低水势忍耐脱水的抗旱方式,并且反应中心可能存在可逆失活和能量陷阱等方式响应水分胁迫,而大果白刺具有高水势延迟脱水特征,其水分胁迫极限阈值RWC为78%;骆驼刺作为当地的优势种对干旱具有较强的适应性和耐受性,而大果白刺并不适宜在长期干旱胁迫或者地下水位波动较大的地区进行引种推广。
英文摘要	Samples of Alhagi sparsifolia and Nitraria roborowskii leaves were colleted on the south fringe of the Taklimakan desert.At different relative water contents(RWC),we investigated the characteristics of the water potential(psi_w),stomatal conductance(G_s)and chlorophyll fluorescence parameters changes. The results indicated that:(1)Under the dehydration stress,the initial G_s value of N.roborowskii was high as 495.7mmol·m~(-2)·s~(-1) and decreased slowly when RWC above 96%;While A.sparsifolias stoma responded quickly to the dehydration stress,it could control the G_s value in 180 mmol·m~(-2)·s~(-1) and had a generally slow decrease.(2)N.roborowskiis initial water potential was higher than A.sparsifolias and could maintain some stability in extent,but when RWC below 84%,itspsi_w began to decrease strongly under the level of A.sparsifolias,which always maintained more slowly.(3)The twos leaves G_s to absolute psi_w showed negative exponential regression relationship and there was a critical point of psi_w to G_s of N. roborowskii as-2.2Mpa,but A.sparsifolia had no clear point.(4)On the natural dehydration,both two showed F_0 rose significantly,F_v/F_m,F_v/F_0 values decreased.N.roborowskii had more severe damage to reaction centers,but A.sparsifolias F_v/F_m value more than 0.1until RWC was 55%,indicating its PSⅡ reaction centers itself was stable,meanwhile,its TR_o/RC,RC/CS_o values posed fluctuate and its RC/CS_o changed insignificantly.N.roborowskiis fluorescence specific activity values increased suddenly and the fluorescence curves distorted when RWC less than 78%.In summary,A.sparsifolia posed low water potential to tolerate dehydration and it may exist reaction centers lose activity reversible and energy trap to carry on heat dissipation and respond water stress,while N.roborowskii showed maintain high water potential to delay dehydration and its RWC point which stands for water stress utmost threshold was 78%.In all,A.sparsifoliaas local dominant species have a better adaptability and tolerance and N.roborowskii is not suitable for the area to introduce and spread where or long term consistent drought or groundwater level fluctuates strongly exist.
中文关键词	荒漠植物 ; 水分胁迫 ; 水分状况 ; 光系统Ⅱ
英文关键词	desert plants water stress water status photosystem Ⅱ
语种	中文
国家	中国
收录类别	CSCD
WOS类目	PLANT SCIENCES
WOS研究方向	Plant Sciences
CSCD记录号	CSCD:4913072
来源机构	中国科学院新疆生态与地理研究所
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/230321
作者单位	1.中国科学院新疆生态与地理研究所, 荒漠与绿洲生态国家重点实验室;;新疆策勒荒漠草地生态系统国家野外科学观测试验站, 乌鲁木齐, 新疆 830011, 中国; 2.中国科学院新疆生态与地理研究所, 荒漠与绿洲生态国家重点实验室, 乌鲁木齐, 新疆 830011, 中国
推荐引用方式 GB/T 7714	鲁建荣,李向义,薛伟,等. 两种荒漠植物叶片脱水下水分生理和PSⅡ活性特征[J]. 中国科学院新疆生态与地理研究所,2013,33(7):1427-1434.
APA	鲁建荣,李向义,薛伟,林丽莎,李磊,&张新林.(2013).两种荒漠植物叶片脱水下水分生理和PSⅡ活性特征.西北植物学报,33(7),1427-1434.
MLA	鲁建荣,et al."两种荒漠植物叶片脱水下水分生理和PSⅡ活性特征".西北植物学报 33.7(2013):1427-1434.